Counterbore and spot-facer tool



8, 1944. E. A. ZEMPEL 2,355,552

- COUNTER BORE AND SPOT FACER TOOL I Filed March 17, 1943lllluliiiiiiiiiiiiii INVENTOR EDWARD A. ZEMPEL ATTORNEYS Patented Aug.8, 1944 UNITED STATES PATENT 0 F'FICE COUNTERBORE AND SPOT-FACER TOOLEdward A. Zempel, Milwaukee, Wis. Application March 1'7, 1943, SerialNo. 479,456

2- Claims.

This invention appertains to machine tools and and held to its originalcuttingposition after sharpening.

A further important object of my invention is the provision of a spotfacer and counterbore tool having a freely removable blade which can beadjusted forwardly as the blade is resharpened, whereby the blade can beused for substantially its entire length before being discharged.

A still further object .of my invention is the provision of anadjustable spot facer and counterbore tool of the above character, whichembodies a minimum number of parts and one which can be manufactured andplaced upon the market at a reasonable cost.

With these and other objects in view, the invention consists in thenovel construction, arrangement and formation of parts, as will behereinafter more specifically described, claimed, and illustrated in theaccompanying drawing, in which drawing:

Figure 1 is a side, elevational view of my complete tool with partsthereof broken away and in section to illustrate structural detail.

Figure 2 is a View similar to Figure 1 but looking at right anglesthereto and showing the use of a removable pilot sleeve for permittingthe tool to be used in different sized openings.

Figure 3 is a side, elevational View of the body or shank of the toolwith the various parts removed therefrom.

Figure 4 is a detail, diametric, sectional view through the tool takenon the line 4-4 of Figure 1 looking in the direction of the arrows.

Figure 5 is an end, elevational view of my novel tool.

Figure 6 is a detail, perspective view of the blade utilized.

Referring to the drawing in detail, wherein similar reference charactersdesignate corresponding parts throughout the several views, the letter Cgenerally indicates my improved counterbore and spot facer tool and thesame includes an elongated cylindrical body l0 having the head ll formedon the forward end thereof and the tapered shank l2 on its opposite endfor insertion in the chuck of a machine.

The cylindrical body I!) is provided with relatively fine threads l3from one end thereof to the other and as illustrated, the threads extendto the head ll. A diametrically extending slot 14 also extendssubstantially the full length of the body and this slot extends into thehead II. The forward end of the head has formed integrally therewith thepilot l5. A centering and blade guiding rib I6 is formed integrally withthe head I l and the pilot [5 and extends into the slot M, for apurpose, which will be more clearly set out. It is to be noted, however,that the rib lfi extends transversely across the slot I4. The head H isprovided with a flat front face and its inner surface is provided witha, tapered annular shoulder I1. The head on opposite sides is providedwith chip clearance grooves l8.

Detachably associated with the body of the tool is the blade l9. Thisblade is formed from a flat piece of tool steel and is axiallybifurcated by an elongated slot 2!]. This slot extends from the forwardend of the blade to a point short of the inner end thereof and hence theblade, when viewed in side elevation, is of a substantially U- shape.The slot 20 defines on the opposite sides thereof cutting edges 2|. Theinner end of the blade, at its corners, is provided with inclinedshoulders 22, for a purpose which will later appear.

The slot 20 has a width substantially equal to the thickness of the ribl6 and the blade is adapted to straddle the rib and the opposite wallsof the slot are adapted to snugly engage the opposite faces of the rib.Likewise, the thickness of the blade is substantially equal to the widthof the slot M in the body of the tool and the blade is adapted to beinserted in said slot [4 and held therein against lateral shifting andchattering by the walls of the slot Hi.

When the blade is inserted in the slot l4 the same is pushed forwardlyinto engagement with the rib it which acts as a guide and centertherefor. After the blade has been inserted in place, the adjusting nut23 is fed forwardly on the shank so as to push the blade forward intofirm contact with seats 24 arranged on opposite sides of the rib [6.Hence the nut 23 is used to accurately adjust the blade forwardly and tohold the same in its set cutting position. The forward face of the nut23 is tapered, as at 25, for en- '24 shown in said figures.

gagement with the shoulders 22 on the blade and the taper of the nut isthe same as the taper of the annular shoulder l1 and thus th nut can befed down to the head as the blade wears from resharpening.

A lock nut 26 is also threaded on the shank into intimate contact withthe adjusting nut 23 after the nut has been threaded to its desiredposition and the lock nut effectively holds the adjusting nut in its setposition against movement.

When it becomes necessary to resharpen the blade l9 it is merelynecessary to back off the nuts 23 and 26 on the 'body away from theblade and to then remove the blade from the body. Obviously, this can beaccomplished without removing the body of the tool on the machine or bychanging of the setting of the tool on the machine. The blade can now besharpened in the ordinary manner and after sharpening can bereassociated with the body of the tool and moved back to its originalcutting position by the nut 23.

Great stress is laid on the manner of holding the blade in position, inthat substantially the entire length of the blade can be used before thesame will have to be discarded. Also the arrangement is such that aminimum number of parts is utilized and the blade is so held thatchattering thereof in the body is eliminated.

Further, as the blade is removed from the body of the tool duringsharpening, the chip clearance grooves 18 are not damaged in any way bysuch resharpening and the holding of this chip clearance at all times isnot efiected.

As the tool will be used in different sized openings, I preferablyprovide a plurality of different .size sleeves 28 for removableassociation with the pilot l5 and these sleeves can be held in place bythe use of a washer 29 and fastening screw 30. As stated, the blade isheld and centered at By referring to Figure 1, it can be seen that thetapered face of the recess 25 corresponds to the incline or taper of theshoulders 22.

Particular stress is laid on the arrangement and 1 formation of the webor rib I6 as not only does this rib or web center and guide the cutting.blade l9 but the same reinforces the head and the pilot.

7 Particular attention is again directed to Figures l and 3 and thearrangement of the seat The cutting edges 2| of the blade extend fromthe side edges of the "blade to the walls of the slot 20 and the innercorners of these cutting edges are received in the seats 24. Hence thecutting edges are active all the way from the side edges of the blade tothe pilot. This prevents the forming of a fin 5 in the work around thepilot.

Changes in details may be made without departing from the spirit or thescope of my invention, but what I claim as new is:

1. A counterbore and spot facer comprising a cylindrical body having anannular head formed on its forward end and a shank on its rear end, saidbody and head being providedwith a diametrically extending bladereceiving slot and said body being threaded from the head to a pointbeyond the slot, a centering and guiding rib at the forward end of saidslot having seats on the opposite sides thereof, the rib extendingtransversely across the slot, a flat blade positioned in said slot andhaving formed therein a longitudinally extending slot extendingsubstantially the full length thereof for receiving the rib, the slot inthe blade defining cutting edges at the forward end of the blade and onthe opposite sides of the slot, and a nut threaded on the body to engagewith the rear end of the blade for moving the blade forwardly intoengagement with said seats, the adjusting nut having its forward faceprovided with a tapered recess and tapered shoulders formed on the rearend of the blade adapted to be engaged by the tapered face of therecess.

2. A counterbore and spot facer comprising a cylindrical body having anannular head formed on its forward end and a shank on its rear end, saidbody and head being provided with a diametrically extending bladereceiving slot and said body being threaded from the head to a pointbeyond the slot, a centering and guiding rib at the forward end of saidslot having seats on the opposite sides thereof, the rib extendingtransversely across the slot, a flat blade positioned in said slot andhaving formed therein a longitudinally extending slot extendingsubstantially the full length thereof for receiving the rib, the slot inthe blade defining cutting edges at the forward end of the blade and onthe opposite sides of the slot, and a nut threaded on the shank toengage with the rear end of the blade for moving the blade forwardlyinto engagement with said seats, the adjusting nut having its forwardface provided with a tapered recess and tapered shoulder formed on therear end of the blade adapted to be engaged by said tapered face, saidhead having an annular tapered shoulder corresponding to the taperedrecess of the adjusting nut.

EDWARD A. ZEMPEL.

